Characterization of Subclinical Cardiac Dysfunction by Speckle Tracking Echocardiography in Patients With Non-severe Acute-Phase Myocarditis.

Subclinical changes in left ventricular (LV) function have been demonstrated in patients with acute-phase myocarditis (AM) despite normal LV ejection fraction. The impact of AM on right ventricular (RV) and left atrial (LA) function has not been well described. This study aimed to assess for subclinical chamber dysfunction by speckle tracking echocardiography and its clinical relevance in this population. Patients with a diagnosis of AM (as per the European Society of Cardiology Working Group on Myocardial and Pericardial Diseases) admitted to our institution from 2013 to 2018 were assessed. Patients with elevated serum troponin, normal coronary assessment, and normal LV ejection fraction on transthoracic echocardiogram were included. Clinical and echocardiographic parameters were compared with healthy age-, gender- and risk-factor matched controls. Global longitudinal strain assessed through speckle tracking echocardiography was performed using vendor independent software (v4.6; TomTec Arena, Munich, Germany). The final cohort consisted of 80 patients (40 AM patients and 40 controls). No significant differences in baseline clinical characteristics were observed between groups. Of the echocardiographic parameters, AM patients had lower LV-global longitudinal strain (p <0.01), lower RV free-wall strain (p = 0.02) and lower peak LA strain (p <0.01). There were no differences in traditional echocardiographic measures of LV, RV, and LA function appreciated between groups. The presence of multichamber involvement was associated with peak Troponin levels (p <0.01). In conclusion, our study demonstrates the presence of global subclinical myocardial dysfunction in patients with AM. Additionally, the presence of multichamber involvement was significantly associated with degree of myocardial necrosis.

Usefulness of Left Atrial Strain to Predict End Stage Renal Failure in Patients With Chronic Kidney Disease.

Left atrial (LA) enlargement predicts adverse cardiovascular events in patients with chronic kidney disease (CKD). The aim of our study was to evaluate the value of LA reservoir strain, a novel measure of LA function, as a prognostic marker for adverse renal outcomes. A total of 280 patients (65.8 ± 12.2years, 63% male) with stable Stage 3 and 4 CKD without prior cardiac history were evaluated with transthoracic echocardiography and prospectively followed for up to 5 years. The primary end point was progressive renal failure, which was the composite of death from renal cause, end-stage renal failure and/or doubling of serum creatinine. Over a mean follow up of 3.9 ± 2.7years, 56 patients reached the composite endpoint. By log rank test, older age, lower baseline eGFR, anemia, diabetes mellitus, higher urinary albumin/creatinine ratio, number of antihypertensive medications, higher indexed left ventricular mass, larger LA volumes, and impaired LA reservoir strain were significant predictors of the composite outcome (p <0.01 for all). Multi-variable Cox regression analysis found LA reservoir strain, eGFR, number of antihypertensive medications and urinary albumin/creatinine ratio were independent predictors for progressive renal failure (p <0.01 for all). Impaired LA reservoir strain was associated with a 2.5-fold higher risk of the composite outcome (HR 2.51, 95% CI 1.19 to 5.30, p = 0.02) and was the only echocardiographic parameter that predicted progressive renal failure independent of established clinical risk factors for end-stage renal failure. Its utility requires validation in high risk CKD patients with cardiac disease.

Left Atrial Reservoir Strain by Speckle Tracking Echocardiography: Association With Exercise Capacity in Chronic Kidney Disease.

Background Left atrial (LA) function plays a pivotal role in modulating left ventricular performance. The aim of our study was to evaluate the relationship between resting LA function by strain analysis and exercise capacity in patients with chronic kidney disease (CKD) and evaluate its utility compared with exercise E/e'. Methods and Results Consecutive patients with stage 3 and 4 CKD without prior cardiac history were prospectively recruited from outpatient nephrology clinics and underwent clinical evaluation and resting and exercise stress echocardiography. Resting echocardiographic parameters including E/e' and phasic LA strain (LA reservoir [LASr], conduit, and contractile strain) were measured and compared with exercise E/e'. A total of 218 (63.9±11.7 years, 64% men) patients with CKD were recruited. Independent clinical parameters associated with exercise capacity were age, estimated glomerular filtration rate, body mass index, and sex (P<0.01 for all), while independent resting echocardiographic parameters included E/e', LASr, and LA contractile strain (P<0.01 for all). Among resting echocardiographic parameters, LASr demonstrated the strongest positive correlation to metabolic equivalents achieved (r=0.70; P<0.01). Receiver operating characteristic curves demonstrated that LASr (area under the curve, 0.83) had similar diagnostic performance as exercise E/e' (area under the curve, 0.79; P=0.20 on DeLong test). A model combining LASr and clinical metrics showed robust association with metabolic equivalents achieved in patients with CKD. Conclusions LASr, a marker of decreased LA compliance is an independent correlate of exercise capacity in patients with stage 3 and 4 CKD, with similar diagnostic value to exercise E/e'. Thus, LASr may serve as a resting biomarker of functional capacity in this population.

Left Atrial Strain Is the Best Predictor of Adverse Cardiovascular Outcomes in Patients with Chronic Kidney Disease.

BACKGROUND: Patients with chronic kidney disease (CKD) are at increased risk of adverse cardiovascular events, which is underestimated by traditional risk stratification algorithms. We sought to determine clinical and echocardiographic predictors of adverse outcomes in CKD patients. METHODS: Two hundred forty-three prospectively recruited stage 3/4 CKD patients (male, 63%; mean age, 59.2 ± 14.4 years) without previous cardiac disease made up the study cohort. All participants underwent a transthoracic echocardiogram, with left ventricular (LV) and left atrial (LA) strain analysis. Participants were followed for 3.9 ± 2.7 years for the primary end point of cardiovascular death and major adverse cardiovascular event (MACE). The secondary end point was the composite of all-cause death and MACE. RESULTS: Fifty-four patients met the primary end point, and 65 the secondary end point. On log-rank tests, older age, diabetes mellitus, anemia, greater LV mass, reduced LV global longitudinal strain, larger indexed LA volume, higher E/e' ratio, and reduced LA reservoir strain (LASr; P < .01 for all) were independent predictors of cardiovascular death and MACE. On multivariable regression analysis of univariate predictors, LASr (P < .01) was the only independent predictor for the primary end point as well as for the secondary end point. Receiver operating characteristic curve analysis showed LASr was a stronger predictor of adverse events (area under the curve [AUC] = 0.84) compared to the Framingham (AUC = 0.58) and Atherosclerotic Cardiovascular Disease (AUC = 0.59) risk scores. CONCLUSIONS: LASr is an independent predictor of cardiovascular death and MACE in CKD patients, superior to clinical risk scores, LV parameters, and LA volume.